In Undertow before versions 7.1.2.CR1, 7.1.2.GA it was found that the fix for CVE-2016-4993 was incomplete and Undertow web server is vulnerable to the injection of arbitrary HTTP headers, and also response splitting, due to insufficient sanitization and validation of user input before the input is used as part of an HTTP header value.

undertow before versions 1.4.18.SP1, 2.0.2.Final, 1.4.24.Final was found vulnerable when using Digest authentication, the server does not ensure that the value of URI in the Authorization header matches the URI in HTTP request line. This allows the attacker to cause a MITM attack and access the desired content on the server.